by Jay Ducharme
(All text and images copyright Jay Ducharme 2019.)


The next ride I chose to tackle was the Puffing Billy, the multi-level train ride that sat between the boats and the Whip. It was the only kiddie ride besides the kiddie coaster that could accomodate adults alongside children. When examining the train car, I again broke it down into its base geometric components and figured it wouldn't be too difficult to recreate. The track on the other hand was a big question mark. It consisted of three rails: two outside rails for the wheels and a center one for power. At my small scale, that would never print properly. So instead I thought of designing it more like a strip of roadway and building it in sections so that I could connect it up onsite, much like a model railroad. That way I could print all the sections as flat pieces and also print all the upper level supports separately. There were two ramps (one up and one down) and the 180-degree turn of the upper section, but everything else was on the ground. The trick would be getting all the measurements correct so it fit together properly.

I started with a sketch that matched the footprint of the model. The pattern of the track was clever, a sort of curvy double oval that gave the sense of a much longer trip than it was. Like the Cutie Caddy and the kiddie coaster, part of the ride (the curve leading back to the station) was perched on the edge of the cliff overlooking the parking lot and as a kid it was always a thrill riding along that edge.

The first part that I modeled was the train. The actual train car had a lot of curvy detail in it. But I left all that out of my model since it would never print. The train took me just a few hours to construct.

I started the track with the straight piece that formed the station. I made the three rails out of elongated cubes and placed them on a flat surface so that they'd print. To make the curves, I used a duplicate of the straight piece but shortened it and then cut the sides at a 12-degree angle. That allowed me to fit the small sections together into a gentle curve. When I got to the inclines, I tilted the track up so that I could size the length correctly. I added the curve and the downslope and then finished off with the curve back to the station. Then I created the trestles so that they fit under the raised track.

Once that was completed, I took apart the raised sections and flattened out the entire layout. That was how I would print it. Once again, the tiny scale proved to be a challenge with several of the smaller trestle sections refusing to print. When I finally got a decent print, I painted the track and trestles green. Then I painted the trains as best I could. When that was dry, I glued the trestles onto the upper track which would make the whole thing easier to install.

With that done, I turned my attention back to the kiddie coaster. Knowing how poorly small detail printed, I approached this design with a more brutal aesthetic. I wanted to make all the parts thick, even if it looked unrealistic on the screen, because I knew that would print correctly. The original structure was lattice-like, which would have been unprintable. So instead I made the track more like a flume trough. I stretched and subdivided a cube in Blender which allowed me to bend it in any direction. Then I simply duplicated that cube over and over, curving it as I needed to. In a short time I had a complete circuit,

Next I created an A frame and duplicated that, sizing and rotating each one as needed, until all the supports were done. They didn't look anything like the actual rather dainty supports, but again I needed them to print. My first printing attempt wasn't very successful. The track itself was broken in places. There was a lot of stringing and the supports were fragmented. So I went back to the drawing board and beefed up the entire structure. It looked ridiculous on the computer, but it actually printed pretty well. Try as I might, I couldn't get the train to print. I redesigned it to make it a bit thicker and I also added a thick bar through it, front to back, allowing me to line them up in my slicer program and print them out as a single train. But the printer couldn't handle something that tiny and extruded tiny formless blobs. So I ordered a new .2 mm nozzle for my printer (half the size of the default nozzle). It arrived in a few days, and the result was dramatically better. It still didn't look much like a train, but there was finally some discernable detail.

Painting the pieces was fairly simple. The original coaster had a yellow track structure with pastel green and blue supports. But most of the yellow had been spattered with grease. The most prominent track color was the silver of the rails, so that's what I went with for the top. I left the raft on the base and painted it dark green, so that it would be easier to affix to the Homasote. Then I painted the train and glued it to the lift hill, and the kiddie coaster was done.

While I was at it, I made a larger version of the Puffing Billy and attached it to a wood base with fake grass and trees. I planned to give it to Jay Collins at some point.

It wasn't until mid-August that I made it back to Heritage Park to install the two rides. I still needed to figure out how I was going to make the station for the kiddie coaster. And I needed to make the pavilion for the Whip. And then I needed to decide what I would tackle next.

There's a slight addendum to this portion: I had been working on the station for the kiddie coaster. It was too small to build out of toothpicks and card stock, so I once again turned to the 3D printer. On my first attempt, the legs were too thin and broke off. So as I did for the coaster track, I beefed up the supports and it printed fine. I painted it and brought it to Heritage Park in September. When I arrived, there was an unpleasant surprise. Evidently an unsupervised child had gotten a hold of the model and had torn up a few trees and the Pizza roof. Obviously, I wasn't too happy about that. Charlie wasn't around. I showed his assistant the damage and she wasn't very happy about it either. They needed that plexiglass cover to prevent further damage. Anyway, I glued the kiddie coaster station into place. It was a bit too tall, but from most people's viewing angle it wouldn't matter. Then I had the assistant help me place the wooden cover (which had been stored off to the side) back onto the model. It would remain safely out of view until they were able to properly protect it.

Remaking Mountain Park